The present invention relates to a machine for producing and dispensing liquid and semi-liquid consumer food products.
The present invention relates in particular, although without limiting the scope of the inventive concept, to machines for producing and dispensing crushed-ice drinks, sorbets, ice creams, soft ice creams, cream, ice cream cakes, yoghurt and the like and to machines for producing and preserving mixtures for ice cream, creams, sauces, soups and mixtures in general and the like.
As is known, machines of the above-mentioned type comprise one or more containers for the basic product, consisting for example of liquid cream, mixtures of products for ice cream, syrups and the like, and a feed circuit along which there are devices, including refrigeration means, for basic product treatment and processing and at the outfeed end of the circuit there are dispensing means, consisting of nozzles or taps designed to allow the end product (whipped cream, ice cream, crushed-ice drink, etc.) to be drawn out.
Such machines comprise a refrigeration system needed to lower the temperature of the basic product.
The refrigeration system of the prior art machines comprises a circuit filled with a suitable refrigerant which is processed according to a known refrigeration cycle.
The refrigerants used are, for example, CFCs (chlorofluorocarbons), fully halogenated and without hydrogen in the molecule (for example, R11, R12, R12B1), HCFCs (hydrochlorofluorocarbons), partly halogenated and containing hydrogen in their molecule (for example, R22), HFCs (hydrofluorocarbons) partly halogenated, without chlorine, and containing hydrogen in the molecule (for example, R32, R134a, R410A, R407C).
Disadvantageously, such refrigerants used in the machines are synthetic and are expensive, and their availability is limited.
Moreover, it should be noticed that these refrigerants have a significant impact on the environment, for example relating to depletion of the atmosphere's ozone layer and an increase in the greenhouse effect.
The refrigerants used are, for example, hydrocarbons (for example, propane R290 and isobutane R600a).
Disadvantageously, such refrigerants used in the machines are inflammable and potentially explosive.